INTRODUCTORY ESSAY. 11 The rashness of some botanists is productive of still more detrimental effects to the science in the case of species; for though a beginner may pause before venturing to institute a genus, it rarely enters into his head to hesitate before pro- posing a new species. Hence the difficulty of determining synonymy is now the greatest obstacle to the progress of systematic botany; and this incubus unfortunately increases from day to day, threatening at* no very distant period so to encumber the science, that a violent effort will be ne- cessary on the part of those who have its interests at heart, to relieve it of a load which materially retards its advance- ment. The number of species described is now so very great, and the descriptions are scattered through such a multitude of books, that even after long research it is difficult to avoid overlooking much that is already known; and when botanists with limited libraries and herbaria institute new species, it is almost certain that the latter will be found to have been already characterized. To such an extent is this carried, that we could indicate several works, in which one half and even more of the species are proposed in ignorance of the labours of other botanists. Indian Botany unfortunately, far from forming an honourable exception in this particular, presents a perfect chaos of new names for well-known plants, and inac- curate or incomplete descriptions of new ones. It must be remembered too that the Ldnnean canon, by which twelve words were allowed for a specific character, is now becoming quite inadequate to the requirements of the science; and that the brief descriptions, which are now so ge- nerally substituted for definitions, unless prepared with the greatest skill, as well as care, and after an inspection of very numcroxis specimen^ seldom express accurately the essential characters of a plant. It is indeed becoming more and more evident, that in the great majority of instances no definition is sufficient to enable inexperienced botanists to determine important principle in view, 'and to imprest* it upon othent j lie hns, however, failed to check the prevalent tendency to the multiplication of genera.